Spiders belong to the arthropod group, and are characterized by having eight legs and singular eyes. While there are nearly 40,000 species of spiders throughout the world, no matter the species, if you find a spider in your bed, it should raise an alarm. Not every spider is venomous; however, some spiders may cause allergic reactions if you're bitten. If you have spiders in your bed, there are several steps you can take to locate where these arachnids are coming from and prevent their entry into your home.

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Spiders tend to make their way to beds for their warmth and darkness.

Why the Bed

The reason a spider may find itself in your bed may vary; however, as stated earlier, spiders are constantly on the lookout for warm and enclosed areas to make their home or hibernate during cold months. Beds are ideal locations for spiders, as these structures offer a warm space, and between the sheets, little light gets through, thus offering an ideal home for these eight-legged arachnids.

Open Windows

One of the main causes of spiders in your home is an open window. During the late summer/early fall months, spiders actively search for winter hibernation spots, which may lead these arachnids into your home. If your bedroom is on the ground floor of your home, spiders are more likely to enter through that window as it is closer to the ground than a window on higher floors. To prevent spiders from entering your home, and ultimately your bed, install window screens on all windows, or keep your windows shut.

Non-Sealing Doors

If doorways leading outside do not fully seal upon closing, the small space located between the door and the door frame is large enough for spiders to creep into. If you live in a heavily wooded area, or have grassy/weedy areas close to your home, spiders will likely venture through these spaces and find themselves in your home. To remedy this situation, install a better-fitting door, or cover spaces between the door and frame with a towel.

Prevention

The University of Minnesota Cooperative Extension says that most spiders that find their way into homes do not pose a threat to the health and vitality of humans. While all spiders contain venom, very few spiders bite people, and most retreat at the presence of a threat. While spiders may not harm you, you may find the presence of these arthropods unnerving. If this is the case, you may prevent the likelihood of spiders in your bed by keeping your room clean -- removing bags, boxes, paper and other forms of clutter. Prevent spider eggs from hatching by vacuuming webbing found throughout the home. In outdoor spaces, make sure you trim shrubbery and other foliage to keep it from coming in contact with your home, and install yellow lights around the perimeter of the home to discourage insects from coming near your home. This will reduce spiders as there will be no insect food to attract them.